package demo1;

import java.util.Scanner;

/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: ASUS
 * Date: 2023-10-11
 * Time: 16:29
 */
public class Test {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        int num = scanner.nextInt();
        int i = 2;
        for (; i < num/2; i++) {
            if (num % i== 0) {
                System.out.println("不是素数！");
                break;
            }
        }
        if (i >= num/2) {
            System.out.println("是素数！");
        }
    }
}
